Information processing device, display device, and electronic device

ABSTRACT

An electronic device including a large display region and with improved portability is provided. An electronic device with improved reliability is provided. 
     An information processing device includes a first film, a panel substrate, and at least a first housing. The panel substrate has flexibility and a display region, and the first film has a visible-light-transmitting property and flexibility. The first housing includes a first slit, the panel substrate includes a region positioned between the first film and a second film, the first slit has a function of storing the region, and one or both of the panel substrate and the first film can slide along the first slit.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/340,227, filed Apr. 8, 2019, now allowed, which is incorporated byreference and is a U.S. National Phase Application under 35 U.S.C. § 371of International Application PCT/IB2017/056459, filed on Oct. 18, 2017,which is incorporated by reference and claims the benefit of a foreignpriority application filed in Japan as Application No. 2016-210222 onOct. 27, 2016.

TECHNICAL FIELD

One embodiment of the present invention relates to an informationprocessing device, a display device, and an electronic device.

Note that one embodiment of the present invention is not limited to theabove technical field. The technical field of one embodiment of theinvention disclosed in this specification and the like relates to anobject, a method, or a manufacturing method. Alternatively, oneembodiment of the present invention relates to a process, a machine,manufacture, or a composition of matter. Thus, more specifically,examples of the technical field of one embodiment of the presentinvention disclosed in this specification include a semiconductordevice, a display device, a light-emitting device, a power storagedevice, a memory device, a driving method thereof, and a manufacturingmethod thereof.

BACKGROUND ART

Electronic devices including display devices have recently beendiversified. One of them is an information processing device such as acellular phone, a smartphone, a tablet terminal, and a wearableterminal.

Examples of the display devices include, typically, a light-emittingdevice including a light-emitting element such as an organic EL (ElectroLuminescence) element or a light-emitting diode (LED), a liquid crystaldisplay device, and electronic paper performing display by anelectrophoretic method or the like. Patent Document 1 and PatentDocument 2 each disclose a flexible light-emitting device using anorganic EL element.

REFERENCES Patent Documents

[Patent Document 1] Japanese Published Patent Application No.2014-197522

[Patent Document 2] Japanese Published Patent Application No.2015-064570

SUMMARY OF INVENTION Problems to be Solved by the Invention

In recent years, information processing devices, display devices, andelectronic devices having large display regions have been particularlyrequired. A large display region offers advantages such as improvedbrowsability and increased amount of information that can be displayed.However, in portable electronic devices, an enlargement of displayregions causes a reduction in portability. For this reason, browsabilityof display and portability are difficult to improve at the same time.

An object of one embodiment of the present invention is to provide anelectronic device with a large display region. Another object is toimprove the portability of an electronic device. Another object is toachieve both an improvement in browsability of display and animprovement in portability. Another object is to provide a novelelectronic device. Another object is to improve the reliability of anelectronic device.

Note that the description of these objects does not preclude theexistence of other objects. Note that one embodiment of the presentinvention does not necessarily achieve all the objects. Note thatobjects other than the above will be apparent from the description ofthe specification, the drawings, the claims, and the like and objectsother than the above can be derived from the description of thespecification, the drawings, the claims, and the like.

Means for Solving the Problems

An information processing device of one embodiment of the presentinvention includes a hinge, a first housing, a second housing, a panelsubstrate, and a first film. The hinge includes a rotation axis, thefirst housing is connected to the second housing through the hinge so asto be rotatable around the rotation axis, the first housing includes afirst slit, and the second housing includes a second slit. The panelsubstrate includes a region overlapping with the first film, the regionis stored in any one or both of the first slit and the second slit, andany one or both of the panel substrate and the first film can slidealong the second slit.

Furthermore, an information processing device of one embodiment of thepresent invention is the above-described information processing deviceincluding a second film. The panel substrate includes a regionpositioned between the first film and the second film.

Furthermore, an information processing device of one embodiment of thepresent invention is the above-described information processing devicein which the first film has flexibility and a visible-light-transmittingproperty. The panel substrate has flexibility and a display region. Thefirst housing includes a first part and a second part, the first partoverlaps with the display region, and the second part overlaps with aperipheral portion of the first part. Furthermore, the second film ispositioned between the display region and the first part, and the secondfilm has flexibility.

Furthermore, in the information processing device of one embodiment ofthe present invention, the first film is fixed to part of the firsthousing. The first film, the second film, and the panel substrate canslide along the second slit when the second housing rotates around therotation axis with respect to the first housing.

Furthermore, in the information processing device of one embodiment ofthe present invention, the first film is fixed to the first housing, thefirst film can slide along the second slit in the second housing whenthe second housing rotates around the rotation axis with respect to thefirst housing, and the second film is fixed to the first housing and thesecond housing.

Furthermore, in the information processing device of one embodiment ofthe present invention, the second housing includes an end portion thatis parallel to the rotation axis, the first film and the panel substrateslide in the second slit, the first film is apart from the end portion,and the panel substrate is apart from the end portion.

Furthermore, in the information processing device of one embodiment ofthe present invention, the second housing rotates around the rotationaxis with respect to the first housing, whereby the first film has aplanar shape or a convex shape on the panel substrate.

Furthermore, the information processing device of one embodiment of thepresent invention includes a circuit board. The circuit board iselectrically connected to the panel substrate, and the circuit board isstored in the first housing.

Furthermore, the information processing device of one embodiment of thepresent invention includes at least one driver circuit. The drivercircuit is provided over the panel substrate, and the panel substrateincludes a curved portion between the driver circuit and the displayregion.

Furthermore, in the information processing device of one embodiment ofthe present invention, the panel substrate includes a curved portionbetween an image signal line driver circuit and the display region.

Furthermore, the information processing device of one embodiment of thepresent invention includes an input portion. The input portion includesa touch sensor, and the touch sensor includes a region overlapping withthe display region.

Furthermore, the information processing device of one embodiment of thepresent invention includes a first flexible printed board and a secondflexible printed board. The first flexible printed board and the secondflexible printed board are stored in the first housing. In theinformation processing device, the first flexible printed board suppliesa control signal to the display region, and the second flexible printedboard supplies a control signal to the touch sensor.

Furthermore, the information processing device of one embodiment of thepresent invention includes one or more of a keyboard, a hardware button,a pointing device, an illuminance sensor, an imaging device, an audioinput device, an eye-gaze input device, and a pose detection device.

Effect of the Invention

According to one embodiment of the present invention, a novelinformation processing device with excellent portability and reliabilitycan be provided. Alternatively, a novel information processing devicewith excellent operability can be provided. Alternatively, a novelinformation processing device, a novel display device, or the like canbe provided. Note that the description of these effects does notpreclude the existence of other effects. Note that one embodiment of thepresent invention does not necessarily achieve all the effects. Notethat effects other than the above will be apparent from the descriptionof the specification, the drawings, the claims, and the like and effectsother than the above can be derived from the description of thespecification, the drawings, the claims, and the like.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B show cross sections of an information processing deviceof an embodiment.

FIGS. 2A and 2B show cross sections of an information processing deviceof an embodiment.

FIGS. 3A and 3B show structures of touch panels that can be used in aninformation processing device of an embodiment.

FIG. 4 shows a housing of an information processing device of anembodiment.

FIGS. 5A-5C show structures of a touch panel that can be used in aninformation processing device of an embodiment.

FIGS. 6A and 6B show structures of a touch panel that can be used in aninformation processing device of an embodiment.

FIGS. 7A-7C show structures of a touch panel that can be used in aninformation processing device of an embodiment.

FIGS. 8A-8C show structures of a touch panel that can be used in aninformation processing device of an embodiment.

FIGS. 9A-9D show a method for manufacturing a foldable device of anembodiment.

FIGS. 10A-10D show a method for manufacturing a foldable device of anembodiment.

FIGS. 11A-11D show a method for manufacturing a foldable device of anembodiment.

FIGS. 12A and 12B show folding of a touch panel of an embodiment.

FIG. 13 shows an electronic device including an input/output device ofan embodiment.

MODE FOR CARRYING OUT THE INVENTION

Embodiments will be described in detail with reference to the drawings.Note that the present invention is not limited to the followingdescription, and it is easily understood by those skilled in the artthat modes and details can be modified in various ways without departingfrom the spirit and scope of the present invention. Accordingly, thepresent invention should not be interpreted as being limited to thedescription of the embodiments below. Note that in the structures of theinvention described below, the same portions or portions having similarfunctions are denoted by the same reference numerals in differentdrawings, and the description thereof is not repeated.

Embodiment 1

In this embodiment, a foldable touch panel that is an informationprocessing device of one embodiment of the present invention will bedescribed with reference to FIG. 1 to FIG. 4.

The touch panel includes a display portion and a touch sensor.

<Description of Cross-Sectional View>

FIG. 1(A) shows a cross-sectional view of one state of a foldable touchpanel of one embodiment of the present invention. FIG. 1(B) is a drawingshowing another state of the foldable touch panel of one embodiment ofthe present invention.

In one embodiment of the present invention, the foldable touch panelincludes a panel substrate 101, a first film 102, a second film 103, afirst housing 104-1, a second housing 104-2, a hinge 105-1, a circuitboard 106, and a flexible substrate FPC 107. The panel substrate 101,the first film 102, and the second film 103 each have flexibility. Thefirst housing 104-1 can rotate around a rotation axis of the hinge 105-1with respect to the second housing 104-2. It can be said that the stateshown in FIG. 1(A) is the state where the information processing deviceis folded around the rotation axis of the hinge 105-1.

In FIG. 1(A), the first housing 104-1 includes a first part 104-1A, asecond part 104-1B, and an end portion 111. The second housing 104-2includes a first part 104-2A, a second part 104-2B, and an end portion110. The first part 104-1A and the first part 104-2A are connected tothe hinge 105-1, and the circuit board 106 and the FPC 107 are stored inthe first part 104-1A. The second part 104-1B included in the firsthousing 104-1 overlaps with a peripheral portion of the first part104-1A. A space is formed between the second part 104-1B and theperipheral portion of the first part 104-1A. The second part 104-2Bincluded in the second housing 104-2 overlaps with a peripheral portionof the first part 104-2A. Another space is formed between the secondpart 104-2B and the peripheral portion of the first part 104-2A. The endportion 111 is positioned between the first part 104-1A and the secondpart 104-1B. The end portion 110 is positioned between the first part104-2A and the second part 104-2B. For example, in the first housing104-1, a space (a slit 108-1) is formed in a region surrounded by thefirst part 104-1A, the second part 104-1B, and the end portion 111. Inthe second housing 104-2, a space (a slit 108-2) is formed in a regionsurrounded by the first part 104-2A, the second part 104-2B, and the endportion 110. In other words, the slit 108-1 is provided in the firsthousing 104-1, and the slit 108-2 is provided in the second housing104-2.

The first film 102, the panel substrate 101, and the second film 103overlap with each other and are stored in the slit 108-1 and the slit108-2.

In the case where a driver circuit is provided on the panel substrate,it may be provided as an in-cell circuit or provided by a COG (Chip OnGlass) method or a COF (Chip On Film) method. FIG. 1(A) and FIG. 1(B)show a socket 109 that is provided with the use of a COG method.

The information processing device of one embodiment of the presentinvention includes the foldable panel substrate 101 and the first film102, which is transparent and has a thickness of 50 μm to 500 μm,preferably 80 μm to 150 μm. The first film 102 prevents mechanicaldamage on the surface of the panel substrate 101 and prevents the panelsubstrate 101 from being lifted up from the first housing 104-1 and thesecond housing 104-2. In addition, the second film 103 can be storedbetween the panel substrate 101 and the first housing 104-1 or thesecond housing 104-2. The panel substrate 101 is interposed between thefirst film 102 and the second film 103 so as to be able to slide. Thus,the panel substrate 101 can be supported by the first housing 104-1 andthe second housing 104-2. The second film 103 can reduce the amount ofdeformation of the panel substrate 101 due to pressing with touch paneloperation. Note that the information processing device of one embodimentof the present invention can have a structure in which mechanical damageon the surface is prevented even with a structure without the secondfilm 103.

In one embodiment of the present invention, the first film 102 and thesecond film 103 are each fixed to a portion in contact with the firsthousing 104-1, thereby supported by the first housing 104-1. As shown inFIG. 1(A), the first film 102 is fixed to the first housing 104-1 with asupport portion 116. The second film 103 is fixed to the first housing104-1 with a support portion 117.

In one embodiment of the present invention, the panel substrate 101 isconnected to the circuit board 106 through the FPC 107. The circuitboard 106 is fixed to the first housing 104-1. The panel substrate 101is supported by the first housing 104-1 with the use of frictiongenerated between a folded portion of the panel substrate 101 and thefirst housing 104-1 in the vicinity of the end portion 111 andconnection between the FPC 107 and the circuit board 106.

In the slit 108-1 included in the first housing 104-1, the first film102 and the panel substrate 101 may be fixed to each other, and thepanel substrate 101 and the second film 103 may be fixed to each other.Thus, the panel substrate 101, the first film 102, and the second film103 can slide on each other in the slit 108-2 included in the secondhousing 104-2. Alternatively, stress applied to the panel substrate withthe folding operation of the information processing device can berelieved. Alternatively, damage on the panel substrate due to the stresscan be prevented.

The first film 102 includes a region that is not fixed to the panelsubstrate 101. When the information processing device is folded whilethe first film 102 and the panel substrate 101 are fixed to each other,the panel substrate 101 is prone to fracture due to stress. In oneembodiment of the present invention, the first film 102 and the panelsubstrate 101 slide when the folding operation of the above informationprocessing device is performed, whereby damage on the panel substrate101 due to stress is reduced.

In the information processing device of one embodiment of the presentinvention, the display portion is visible through the first film 102.That is, the first film 102 transmits light with a wavelength in thevisible light range. FIG. 2(A) is the state where the informationprocessing device is folded so that the display surface is concave. Inthis state, the first film 102 is closer to the end portion 110 than thesecond film 103 is. FIG. 2(B) is the state where the informationprocessing device is folded so that the display surface is convex. Inthis state, the second film 103 is closer to the end portion 110 thanthe first film 102 is. The first film 102, the second film 103, and thepanel substrate 101 slide on each other in this manner; it is thuspossible to reduce bending stress, compressive stress, and tensilestress that are applied to the panel substrate 101.

<Description of Top View of Panel Substrate>

In this embodiment, a touch panel 300 can be used as the panel substrate101, for example (see FIG. 3(A)). Alternatively, a touch panel 400 canbe used (see FIG. 3(B)). The touch panel 300 and the touch panel 400each include a display portion 301.

The touch panel 300 or the touch panel 400 includes a touch sensor, andthe touch sensor includes a region overlapping with the display portion301. For example, a sheet-like capacitive touch sensor that overlapswith a display panel can be used. Alternatively, what is called anin-cell touch panel can be used. The in-cell touch panel has a touchsensor function. For example, a capacitive touch sensor may be used, oran optical touch sensor using a photoelectric conversion element may beused. Specifically, a photoelectric conversion element can be used foran optical touch sensor (see FIG. 3(A) or FIG. 3(B)). For example, theoptical touch sensor includes the display portion 301, and the displayportion 301 includes a plurality of pixels 302 and a plurality ofimaging pixels 308. The imaging pixels 308 can sense a finger touchingthe display portion 301, a finger held over the display portion 301, orthe like.

Each of the pixels 302 includes a plurality of sub-pixels (e.g., asub-pixel 302R), and the sub-pixels include light-emitting elements andpixel circuits.

The pixel circuits are electrically connected to wirings that can supplyselection signals and wirings that can supply image signals, and thepixel circuits supply power for driving the light-emitting elements.

The touch panel 300 shown in FIG. 3(A) includes a scan line drivercircuit 303 g(1) and an image signal line driver circuit 303 s(1). Thescan line driver circuit 303 g(1) can supply selection signals to thepixels 302. The image signal line driver circuit 303 s(1) can supplyimage signals to the pixels 302, and the touch panel 400 shown in FIG.3(B) includes a scan line driver circuit and an image signal line drivercircuit. The scan line driver circuit can supply selection signals tothe pixels 302. The image signal line driver circuit can supply imagesignals to the pixels 302. In the case of provision, the touch panel 400includes a region 401(1) and a region 401(2) in each of which the socket109 is placed, and the driver circuits are provided in the regions by aCOG method.

The imaging pixels 308 include photoelectric conversion elements andimaging pixel circuits, and the imaging pixel circuits drive thephotoelectric conversion elements.

The imaging pixel circuits are electrically connected to wirings thatcan supply control signals and wirings that can supply power supplypotentials.

For example, a signal for selecting a predetermined imaging pixelcircuit to read out a recorded imaging signal, a signal for initializingan imaging pixel circuit, and a signal for determining time for animaging pixel circuit to sense light can be used as the control signals.

The touch panel 300 or the touch panel 400 includes an imaging pixeldriver circuit 303 g(2) and an imaging signal line driver circuit 303s(2). The imaging pixel driver circuit 303 g(2) can supply controlsignals to the imaging pixels 308. The imaging signal line drivercircuit 303 s(2) can read out imaging signals.

The touch panel 300 or the touch panel 400 can be folded at a regionindicated by a line segment 406 or a line segment 407. For example, aregion indicated by the line segment 406 is placed in the vicinity ofthe end portion 111 and a region indicated by the line segment 407 isplaced in the vicinity of the hinge 105-1, so that the touch panel 300or the touch panel 400 can be folded.

The touch panel 300 can be folded at the region indicated by the linesegment 406. For example, the touch panel 300 can be folded at a portionbetween a region where the scan line driver circuit 303 g(1) and theimage signal line driver circuit 303 s(1) are placed and a region wherethe display portion is placed. The touch panel 400 can be folded at aportion between a region where the region 401(1) and the region 401(2)are placed and a region where the display portion is placed.Accordingly, the area of the second part 104-1B can be reduced.

Alternatively, the area of the region where the scan line driver circuit303 g(1) and the image signal line driver circuit 303 s(1) are placed inthe touch panel 300 can be larger than the area of the second part104-1B. Alternatively, the area of the region where the region 401(1)and the region 401(2) are placed in the touch panel 400 can be largerthan the area of the second part 104-1B.

<Description of Top View of Housing>

FIG. 4 shows the first housing 104-1, the second housing 104-2, thehinge 105-1, the slit 108-1, the slit 108-2, and the end portion 110.

The hinge 105-1 is connected to one side of the second housing 104-2,and the slit 108-2 is provided on other three sides of the secondhousing 104-2. The end portion 110 is provided parallel to the rotationaxis of the hinge 105-1. The hinge 105-1 is connected to one side of thefirst housing 104-1, and the slit 108-1 is provided on other three sidesof the first housing 104-1. The end portion 111 is provided parallel tothe rotation axis of the hinge 105-1.

The panel substrate 101, the first film 102, and the second film 103 arefixed to the first housing 104-1. Accordingly, the distance between theend portion 111 and the panel substrate 101, the distance between theend portion 111 and the first film 102, and the distance between the endportion 111 and the second film 103 do not change even when theinformation processing device is folded at the hinge 105-1. By contrast,the panel substrate 101, the first film 102, and the second film 103 arenot fixed to the second housing 104-2. Accordingly, when the informationprocessing device is folded at the hinge 105-1, the distance between theend portion 110 and the panel substrate 101, the distance between theend portion 110 and the first film 102, and the distance between the endportion 110 and the second film 103 change. For example, as the distancebetween the rotation axis of the hinge 105-1 and the panel substrate 101becomes longer, the distance between the end portion 110 and the panelsubstrate 101 changes more largely.

Note that in the case where high bending stress, compressive stress, andtensile stress are not applied to the second film 103 when theinformation processing device is folded at the hinge 105-1, the secondfilm 103 may be fixed to the first housing 104-1 and the second housing104-2.

FIG. 1(A), FIG. 1(B), and FIG. 4 simply show the hinge 105-1. In thestate shown in FIG. 1(B), the rotation axis of the hinge 105-1 overlapswith the panel substrate 101. With this configuration, the slidingdistance of the panel substrate 101, the sliding distance of the firstfilm 102, and the sliding distance of the second film 103 with thefolding operation of the information processing device can be reduced.

The panel substrate 101 is apart from the end portion 110, the firstfilm 102 is apart from the end portion 110, and the second film 103 isapart from the end portion 110. Thus, even when the panel substrate 101,the first film 102, and the second film 103 slide with the foldingoperation of the information processing device, neither the panelsubstrate 101, the first film 102, nor the second film 103 comes incontact with the end portion 110. The end portion of the first film 102always overlaps with the second part 104-2B. Accordingly, the endportions of the panel substrate 101, the first film 102, and the secondfilm 103 can be prevented from being detached from the slit 108-2 orcolliding with the end portion of the second part 104-2B. Alternatively,neither the panel substrate 101, the first film 102, nor the second film103 comes in contact with the end portion 110. Alternatively, it ispossible to prevent warping, degradation, and fracture of the panelsubstrate 101, the first film 102, and the second film 103 due to acontact with the end portion 110.

For example, the display portion can be provided over the panelsubstrate 101, and the touch panel can be provided over the first film102. Note that the first film 102 and the panel substrate 101 slide;thus, the position of the touch panel relative to the display portion isshifted with the slide in some cases. When positional information isinput to the touch panel with the position shifted, unintendedinformation is input in some cases. For example, the touch panel and thedisplay portion can be provided over the panel substrate 101. Thus, thepositional shift of the touch panel relative to the display portion canbe eliminated, which is preferable.

The information processing device of one embodiment of the presentinvention may be constituted only by the first film 102 and the panelsubstrate 101. In that case, the panel substrate 101 is in contact withthe first film 102 so as to be able to slide, and supported by the firsthousing 104-1 and the second housing 104-2.

The information processing device of one embodiment of the presentinvention may be constituted only by three or more films and the panelsubstrate 101. In that case, the panel substrate 101 is in contact witha film that is in contact with one surface thereof and a film that is incontact with the opposite surface thereof so as to be able to slide oneach other, and supported by the first housing 104-1 and the secondhousing 104-2.

The information processing device of one embodiment of the presentinvention may have a structure in which a plurality of hinges areprovided and three or more housings are included. When one of theconnected housings of the information processing device is referred toas a first housing, a structure may be employed in which the first film102 and the panel substrate 101 can slide in a slit of a housing otherthan the first housing.

Embodiment 2

In this embodiment, a structure of a foldable touch panel included in aninformation processing device of one embodiment of the present inventionwill be described with reference to FIG. 5.

FIG. 5(A) is a top view illustrating a structure of the touch panel thatcan be used in the information processing device of one embodiment ofthe present invention. The components in FIG. 5(A) correspond to thosein FIG. 3(A).

FIG. 5(B) is a cross-sectional view along the section line A-B and thesection line C-D in FIG. 5(A).

FIG. 5(C) is a cross-sectional view along the section line E-F in FIG.5(A).

<Description of Cross-Sectional View>

The touch panel 300 includes a substrate 310 and a counter substrate 370that faces the substrate 310 (see FIG. 5(B)).

The use of a flexible material for the substrate 310 and the countersubstrate 370 can give the touch panel 300 flexibility.

Note that when the flexible touch panel 300 is changed in its form,stress is applied to a functional element provided in the touch panel300. Preferably, the functional element is placed substantially at themidpoint between the substrate 310 and the counter substrate 370, inwhich case a change in the form of the functional element can beinhibited.

Furthermore, materials with a small difference in coefficient of linearexpansion are preferably used for the substrate 310 and the countersubstrate 370. The coefficient of linear expansion of the materials ispreferably lower than or equal to 1×10⁻³/K, further preferably lowerthan or equal to 5×10⁻⁵/K, and still further preferably lower than orequal to 1×10⁻⁵/K.

For example, materials that contain polyester, polyolefin, polyamide(nylon, aramid, or the like), polyimide, polycarbonate, polyurethane, anacrylic resin, an epoxy resin, or a resin having a siloxane bond, suchas silicone, can be used for the substrate 310 and the counter substrate370.

The substrate 310 is a stacked body in which a flexible substrate 310 b,a barrier film 310 a that prevents diffusion of impurities intolight-emitting elements, and a resin layer 310 c that bonds thesubstrate 310 b and the barrier film 310 a together are stacked.

The counter substrate 370 is a stacked body of a flexible base 370 b, abarrier film 370 a that prevents diffusion of impurities into thelight-emitting elements, and a resin layer 370 c that bonds the base 370b and the barrier film 370 a together (see FIG. 5(B)).

A sealant 360 bonds the counter substrate 370 and the substrate 310together. The sealant 360 has a higher refractive index than the air andalso serves as a layer having an optical adhesive function. The pixelcircuits and the light-emitting elements (e.g., a first light-emittingelement 350R) are positioned between the substrate 310 and the countersubstrate 370.

<Structure of Pixel>

Each of the pixels 302 includes a sub-pixel 302R, a sub-pixel 302G, anda sub-pixel 302B (see FIG. 5(C)). The sub-pixel 302R includes alight-emitting module 380R, the sub-pixel 302G includes a light-emittingmodule 380G, and the sub-pixel 302B includes a light-emitting module380B.

For example, the sub-pixel 302R includes the first light-emittingelement 350R and the pixel circuit including a transistor 302 t that cansupply electric power to the first light-emitting element 350R (see FIG.5(B)). The light-emitting module 380R includes the first light-emittingelement 350R and an optical element (e.g., a first coloring layer 367R).

The first light-emitting element 350R includes a first lower electrode351R, an upper electrode 352, and a layer 353 containing alight-emitting organic compound between the first lower electrode 351Rand the upper electrode 352 (see FIG. 5(C)).

The layer 353 containing a light-emitting organic compound includes alight-emitting unit 353 a, a light-emitting unit 353 b, and anintermediate layer 354 between the light-emitting unit 353 a and thelight-emitting unit 353 b.

The light-emitting module 380R includes the first coloring layer 367R onthe counter substrate 370. The coloring layer transmits light with aparticular wavelength, and a layer that selectively transmits light ofred, green, blue, or the like can be used, for example. Alternatively, aregion that transmits light emitted from the light-emitting element asit is may be provided.

The light-emitting module 380R, for example, includes the sealant 360that is in contact with the first light-emitting element 350R and thefirst coloring layer 367R.

The first coloring layer 367R is in a position overlapping with thefirst light-emitting element 350R. Accordingly, part of light emittedfrom the first light-emitting element 350R passes through the sealant360, which also serves as a layer having an optical adhesive function,and the first coloring layer 367R and is emitted to the outside of thelight-emitting module 380R as indicated by arrows in the drawings. Theinformation processing device of one embodiment of the present inventionincludes the first film 102 in the direction of the arrows.

<Structure of Display Panel>

The touch panel 300 includes a light-blocking layer 367BM on the countersubstrate 370. The light-blocking layer 367BM is provided to surroundthe coloring layer (e.g., the first coloring layer 367R).

The touch panel 300 includes an anti-reflective layer 367 p in aposition overlapping with the display portion 301. As theanti-reflective layer 367 p, for example, a circular polarizing platecan be used.

The touch panel 300 includes an insulating film 321. In FIG. 5(B), theinsulating film 321 covers the transistor 302 t. Note that theinsulating film 321 can be used as a layer for reducing unevennesscaused by the pixel circuits. An insulating film on which a layer thatcan inhibit diffusion of impurities into the transistor 302 t and thelike is stacked can be used as the insulating film 321.

The touch panel 300 includes the light-emitting elements (e.g., thefirst light-emitting element 350R) over the insulating film 321.

The touch panel 300 includes, over the insulating film 321, a partitionwall 328 that overlaps with an end portion of the first lower electrode351R (see FIG. 5(C)). The touch panel 300 further includes, over thepartition wall 328, a spacer 329 that controls the distance between thesubstrate 310 and the counter substrate 370.

<Structure of Image Signal Line Driver Circuit>

The image signal line driver circuit 303 s(1) includes a transistor 303t and a capacitor 303 c. Note that the driver circuit and the pixelcircuits can be formed in the same process and over the same substrate.

<Structure of Imaging Pixel>

The imaging pixels 308 each include a photoelectric conversion element308 p and an imaging pixel circuit for sensing light emitted to thephotoelectric conversion element 308 p. The imaging pixel circuitincludes a transistor 308 t.

For example, a pin photodiode can be used as the photoelectricconversion element 308 p.

<Other Components>

The touch panel 300 includes a wiring 311 that can supply a signal, andthe wiring 311 is provided with a terminal 319. Note that an FPC 309(1)that can supply signals such as an image signal and a synchronizationsignal is electrically connected to the terminal 319. The terminal 319may be connected to the FPC 309(1) and an FPC 309(2) separately, or maybe connected to one FPC 309.

Note that a printed wiring board (PWB) may be bonded to the FPC 309(1).

Transistors formed in the same process can be used as the transistorssuch as the transistor 302 t, the transistor 303 t, and the transistor308 t.

Transistors having a bottom-gate structure, a top-gate structure, or thelike can be used.

A variety of semiconductors can be used in the transistors. For example,an oxide semiconductor, single crystal silicon, polysilicon, amorphoussilicon, or the like can be used.

Note that this embodiment can be combined with the other embodiments inthis specification as appropriate.

Embodiment 3

In this embodiment, a structure of a foldable touch panel that can beused for the panel substrate included in the information processingdevice of one embodiment of the present invention will be described withreference to FIG. 6 and FIG. 7.

FIG. 6(A) is a perspective view of a touch panel 500 exemplified in thisembodiment. Note that FIG. 6 shows main components for simplicity. FIG.6(B) is a perspective view of the touch panel 500.

FIG. 7(A) is a cross-sectional view of the touch panel 500 along X1-X2in FIG. 6(A).

The touch panel 500 includes a display portion 501 and a touch sensor595 (see FIG. 6(B)). Furthermore, the touch panel 500 includes asubstrate 510, a substrate 570, and a substrate 590. Note that thesubstrate 510, the substrate 570, and the substrate 590 each haveflexibility.

The display portion 501 includes the substrate 510 and a plurality ofpixels, a plurality of wirings 511 through which signals can be suppliedto the pixels, and an image signal line driver circuit 503 s(1) over thesubstrate 510. The plurality of wirings 511 are led to a peripheralportion of the substrate 510, and some of them form a terminal 519. Theterminal 519 is electrically connected to an FPC 509(1).

<Touch Sensor>

The substrate 590 includes the touch sensor 595 and a plurality ofwirings 598 electrically connected to the touch sensor 595. Theplurality of wirings 598 are led to a peripheral portion of thesubstrate 590, and some of them form a terminal. Then, the terminal iselectrically connected to an FPC 509(2). Note that in FIG. 6(B),electrodes, wirings, and the like of the touch sensor 595 provided onthe back surface side of the substrate 590 (the surface side that facesthe substrate 510) are indicated by solid lines for simplicity.

As the touch sensor 595, for example, a capacitive touch sensor can beused. Examples of the capacitive touch sensor include a surfacecapacitive touch sensor and a projected capacitive touch sensor.

Examples of the projected capacitive touch sensor include aself-capacitive touch sensor and a mutual-capacitive touch sensor, whichdiffer mainly in the driving method. The use of a mutual-capacitivetouch sensor is preferred because multiple points can be sensedsimultaneously.

The case of using a projected capacitive touch sensor will be describedbelow with reference to FIG. 6(B).

Note that a variety of sensors that can sense the proximity or touch ofa sensing target such as a finger can be used.

The projected capacitive touch sensor 595 includes electrodes 591 andelectrodes 592. The electrodes 591 are electrically connected to any ofthe plurality of wirings 598, and the electrodes 592 are electricallyconnected to any of the other wirings 598.

The electrodes 592 each have a shape of a plurality of quadranglesrepetitively arranged in one direction with corners being connected asshown in FIGS. 6(A) and 6(B).

The electrodes 591 each have a quadrangular shape and are repetitivelyarranged in the direction intersecting with the direction in which theelectrodes 592 extend.

A wiring 594 electrically connects two electrodes 591 between which theelectrode 592 is sandwiched. Here, the electrodes 591 and the electrode592 preferably have shapes such that the area of the intersectingportion of the electrode 592 and the wiring 594 is as small as possible.Such a structure allows a reduction in the area of a region where theelectrodes are not provided, reducing unevenness in transmittance. As aresult, unevenness in luminance of light transmitted through the touchsensor 595 can be reduced.

Note that the shapes of the electrodes 591 and the electrodes 592 arenot limited to the above and can be a variety of shapes. For example, astructure may be employed in which the plurality of electrodes 591 arearranged so that a space is formed as little as possible, and theplurality of electrodes 592 are provided with an insulating layerpositioned between the electrodes 591 and the electrodes 592 and arespaced apart from each other to form a region not overlapping with theelectrodes 591. In that case, a dummy electrode that is electricallyinsulated from these electrodes is preferably provided between twoadjacent electrodes 592, whereby the area of a region having a differenttransmittance can be reduced.

The structure of the touch sensor 595 will be described with referenceto FIG. 7.

The touch sensor 595 includes the substrate 590, the electrodes 591 andthe electrodes 592 provided in a staggered arrangement on the substrate590, an insulating layer 593 covering the electrodes 591 and theelectrodes 592, and the wiring 594 that electrically connects theadjacent electrodes 591.

A resin layer 597 bonds the substrate 590 to the substrate 570 such thatthe touch sensor 595 overlaps with the display portion 501.

The electrodes 591 and the electrodes 592 are formed using a conductivematerial having a light-transmitting property. As a conductive materialhaving a light-transmitting property, a conductive oxide such as indiumoxide, indium tin oxide, indium zinc oxide, zinc oxide, or zinc oxide towhich gallium is added can be used. Note that a film containing graphenecan also be used. The film containing graphene can be formed, forexample, by reducing a film containing graphene oxide that is formedinto a film shape. As a reducing method, a method in which heat isapplied or the like can be employed.

The electrodes 591 and the electrodes 592 can be formed by depositing aconductive material having a light-transmitting property on thesubstrate 590 by a sputtering method and then removing an unnecessaryportion by any of various patterning techniques such as aphotolithography method.

As a material used for the insulating layer 593, a resin such as anacrylic resin or an epoxy resin, a resin having a siloxane bond, such assilicone, and inorganic insulating materials such as silicon oxide,silicon oxynitride, and aluminum oxide can be used, for example.

Openings that reach the electrodes 591 are provided in the insulatinglayer 593, and the wiring 594 electrically connects the adjacentelectrodes 591. A conductive material having a light-transmittingproperty can be suitably used for the wiring 594 because the apertureratio of the touch panel can be increased. Furthermore, a material thathas higher conductivity than the electrodes 591 and the electrodes 592can be suitably used for the wiring 594 because electrical resistancecan be reduced.

One electrode 592 extends in one direction, and the plurality ofelectrodes 592 are provided in the form of stripes.

The wiring 594 is provided to intersect with the electrode 592.

A pair of electrodes 591 are provided with one electrode 592 sandwichedtherebetween, and the wiring 594 electrically connects the pair ofelectrodes 591.

Note that the plurality of electrodes 591 are not necessarily arrangedin the direction orthogonal to one electrode 592 and may be arranged toform an angle less than 90°.

One wiring 598 is electrically connected to the electrodes 591 or theelectrodes 592. Part of the wiring 598 serves as a terminal. For thewiring 598, a metal material such as aluminum, gold, platinum, silver,nickel, titanium, tungsten, chromium, molybdenum, iron, cobalt, copper,or palladium or an alloy material containing any of the metal materialscan be used.

Note that an insulating layer that covers the insulating layer 593 andthe wiring 594 can be provided to protect the touch sensor 595.

Although not shown in FIG. 7, a connection layer 599 electricallyconnects the wiring 598 and the FPC 509(2).

As the connection layer 599, various anisotropic conductive films (ACF),anisotropic conductive pastes (ACP), and the like can be used.

The resin layer 597 has a light-transmitting property. For example, athermosetting resin or an ultraviolet curable resin can be used;specifically, an acrylic resin, polyurethane, an epoxy resin, a resinhaving a siloxane bond, such as silicone, or the like can be used.

<Display Portion>

The display portion 501 includes a plurality of pixels arranged in amatrix. Each of the pixels includes a display element and a pixelcircuit driving the display element.

In this embodiment, the case where an organic electroluminescent elementthat emits white light is used as a display element is described;however, the display element is not limited thereto.

For example, organic electroluminescent elements with different emissioncolors may be used in sub-pixels so that the color of emitted lightdiffers between the sub-pixels.

Other than organic electroluminescent elements, various display elementssuch as display elements (also referred to as electronic ink) thatperform display by an electrophoretic method, an electrowetting method,or the like, shutter type MEMS display elements, optical interferencetype MEMS display elements, and liquid crystal elements can be used asthe display element. Furthermore, application to a transmissive liquidcrystal display, a transflective liquid crystal display, a reflectiveliquid crystal display, a direct-view liquid crystal display, or thelike is possible. Note that in the case where a transflective liquidcrystal display or a reflective liquid crystal display is provided, someor all of pixel electrodes function as reflective electrodes. Forexample, some or all of pixel electrodes contain aluminum, silver, orthe like. Moreover, in such a case, a memory circuit such as SRAM can beprovided below the reflective electrodes. Thus, the power consumptioncan be further reduced. A structure suitable for employed displayelements, which is selected from a variety of pixel circuits, can beused.

In the display portion, an active matrix method in which an activeelement is included in a pixel or a passive matrix method in which anactive element is not included in a pixel can be used.

In an active matrix method, as an active element (a non-linear element),not only a transistor but also various active elements (non-linearelements) can be used. For example, an MIM (Metal Insulator Metal), aTFD (Thin Film Diode), or the like can also be used. These elements havea small number of manufacturing steps, resulting in reducedmanufacturing costs or improved yield. Alternatively, the aperture ratiocan be increased because these elements have small element sizes, whichreduces power consumption or achieves higher luminance.

As a method other than the active matrix method, the passive matrixmethod in which an active element (a non-linear element) is not used canalso be used. Since an active element (a non-linear element) is notused, the number of manufacturing steps is small, resulting in reducedmanufacturing costs or improved yield. Alternatively, the aperture ratiocan be increased because an active element (a non-linear element) is notused, which reduces power consumption or achieves higher luminance, forexample.

Flexible materials can be suitably used for the substrate 510 and thesubstrate 570.

Materials with which passage of impurities is inhibited can be suitablyused for the substrate 510 and the substrate 570. For example, materialswith a vapor permeability lower than or equal to 10⁻⁵ g/(m²·day),preferably lower than or equal to 10⁻⁶ g/(m²·day) can be suitably used.

Materials having substantially the same coefficients of linear expansioncan be suitably used for the substrate 510 and the substrate 570. Forexample, materials with a coefficient of linear expansion lower than orequal to 1×10⁻³/K, preferably lower than or equal to 5×10⁻⁵/K, andfurther preferably lower than or equal to 1×10⁻⁵/K can be suitably used.

The substrate 510 is a stacked body in which a flexible substrate 510 b,a barrier film 510 a that prevents diffusion of impurities intolight-emitting elements, and a resin layer 510 c that bonds thesubstrate 510 b and the barrier film 510 a together are stacked.

For example, polyester, polyolefin, polyamide (nylon, aramid, or thelike), polyimide, polycarbonate, an acrylic resin, polyurethane, anepoxy resin, or a resin having a siloxane bond, such as silicone, can beused for the resin layer 510 c.

The substrate 570 is a stacked body including a flexible substrate 570b, a barrier film 570 a that prevents diffusion of impurities intolight-emitting elements, and a resin layer 570 c that bonds thesubstrate 570 b and the barrier film 570 a together.

A sealant 560 bonds the substrate 570 and the substrate 510 together.The sealant 560 has a higher refractive index than the air. In the caseof extracting light to the sealant 560 side, the sealant 560 also servesas a layer having an optical adhesive function. The pixel circuits andthe light-emitting elements (e.g., a first light-emitting element 550R)are positioned between the substrate 510 and the substrate 570.

<Structure of Pixel>

A pixel includes a sub-pixel 502R, and the sub-pixel 502R includes alight-emitting module 580R.

The sub-pixel 502R includes the first light-emitting element 550R andthe pixel circuit including a transistor 502 t that can supply electricpower to the first light-emitting element 550R. The light-emittingmodule 580R includes the first light-emitting element 550R and anoptical element (e.g., a first coloring layer 567R).

The first light-emitting element 550R includes a lower electrode, anupper electrode, and a layer containing a light-emitting organiccompound between the lower electrode and the upper electrode.

The light-emitting module 580R includes the first coloring layer 567R inthe light extraction direction. The coloring layer transmits light witha particular wavelength, and a layer that selectively transmits light ofred, green, blue, or the like can be used, for example. Note that aregion that transmits light emitted from the light-emitting element asit is may be provided in another sub-pixel.

In the case where the sealant 560 is provided on the light extractionside, the sealant 560 is in contact with the first light-emittingelement 550R and the first coloring layer 567R.

The first coloring layer 567R is in a position overlapping with thefirst light-emitting element 550R. Accordingly, part of light emittedfrom the first light-emitting element 550R passes through the firstcoloring layer 567R and is emitted to the outside of the light-emittingmodule 580R as indicated by an arrow in the drawing. The informationprocessing device of one embodiment of the present invention includesthe first film 102 in the direction of the arrow.

<Structure of Display Portion>

The display portion 501 includes a light-blocking layer 567BM in thelight extraction direction. The light-blocking layer 567BM is providedto surround the coloring layer (e.g., the first coloring layer 567R).

The display portion 501 includes an anti-reflective layer 567 p in aposition overlapping with the pixels. As the anti-reflective layer 567p, a circular polarizing plate can be used, for example.

The display portion 501 includes an insulating film 521. The insulatingfilm 521 covers the transistor 502 t. Note that the insulating film 521can be used as a layer for reducing unevenness caused by the pixelcircuits. A stacked-layer film including a layer that can inhibitdiffusion of impurities can be used as the insulating film 521. This caninhibit a reduction in the reliability of the transistor 502 t or thelike due to diffusion of impurities.

The display portion 501 includes the light-emitting elements (e.g., thefirst light-emitting element 550R) over the insulating film 521.

The display portion 501 includes, over the insulating film 521, apartition wall 528 that overlaps with an end portion of the lowerelectrode. The display portion 501 further includes, over the partitionwall 528, a spacer that controls the distance between the substrate 510and the substrate 570.

<Structure of Scan Line Driver Circuit>

A scan line driver circuit 503 g(1) includes a transistor 503 t and acapacitor 503 c. Note that the driver circuit and the pixel circuits canbe formed in the same process and over the same substrate.

<Other Components>

The display portion 501 includes the wirings 511 that can supplysignals, and the wirings 511 are provided with the terminal 519. Notethat the FPC 509(1) through which signals such as an image signal and asynchronization signal can be supplied is electrically connected to theterminal 519.

Note that a printed wiring board (PWB) may be bonded to the FPC 509(1).

The display portion 501 includes wirings such as scan lines, signallines, and power supply lines. Various conductive films can be used forthe wirings.

Specifically, a metal element selected from aluminum, chromium, copper,tantalum, titanium, molybdenum, tungsten, nickel, yttrium, zirconium,silver, and manganese; an alloy containing the above-described metalelements as its component; an alloy containing the above-described metalelements in combination; or the like can be used. In particular, one ormore elements selected from aluminum, chromium, copper, tantalum,titanium, molybdenum, and tungsten are preferably contained. Inparticular, an alloy of copper and manganese is suitable formicrofabrication with the use of a wet etching method.

Specifically, a two-layer structure in which a titanium film is stackedover an aluminum film, a two-layer structure in which a titanium film isstacked over a titanium nitride film, a two-layer structure in which atungsten film is stacked over a titanium nitride film, a two-layerstructure in which a tungsten film is stacked over a tantalum nitridefilm or a tungsten nitride film, a three-layer structure of a titaniumfilm, an aluminum film stacked over the titanium film, and a titaniumfilm further formed thereover, or the like can be used.

Specifically, a stacked-layer structure in which an alloy film or anitride film that combines one or more selected from titanium, tantalum,tungsten, molybdenum, chromium, neodymium, and scandium is stacked overan aluminum film can be used.

Furthermore, a conductive material that contains indium oxide, tinoxide, or zinc oxide and has a light-transmitting property may be used.

Modification Example 1 of Display Portion

A variety of transistors can be used in the display portion 501.

The structure in which bottom-gate transistors are used in the displayportion 501 is illustrated in FIG. 7(A) and FIG. 7(B).

For example, a semiconductor layer containing an oxide semiconductor,amorphous silicon, or the like can be used in the transistor 502 t andthe transistor 503 t illustrated in FIG. 7(A).

For example, a film represented by an In-M-Zn oxide that contains atleast indium (In), zinc (Zn), and M (a metal such as Al, Ga, Ge, Y, Zr,Sn, La, Ce, or Hf) is preferably included. Alternatively, both In and Znare preferably contained.

Examples of a stabilizer include gallium (Ga), tin (Sn), hafnium (Hf),aluminum (Al), and zirconium (Zr). Other examples of the stabilizerinclude lanthanoids such as lanthanum (La), cerium (Ce), praseodymium(Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd),terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm),ytterbium (Yb), and lutetium (Lu).

As an oxide semiconductor included in an oxide semiconductor film, forexample, an In—Ga—Zn-based oxide, an In—Al—Zn-based oxide, anIn—Sn—Zn-based oxide, an In—Hf—Zn-based oxide, an In—La—Zn-based oxide,an In—Ce—Zn-based oxide, an In—Pr—Zn-based oxide, an In—Nd—Zn-basedoxide, an In—Sm—Zn-based oxide, an In—Eu—Zn-based oxide, anIn—Gd—Zn-based oxide, an In—Tb—Zn-based oxide, an In—Dy—Zn-based oxide,an In—Ho—Zn-based oxide, an In—Er—Zn-based oxide, an In—Tm—Zn-basedoxide, an In—Yb—Zn-based oxide, an In—Lu—Zn-based oxide, anIn—Sn—Ga—Zn-based oxide, an In—Hf—Ga—Zn-based oxide, anIn—Al—Ga—Zn-based oxide, an In—Sn—Al—Zn-based oxide, anIn—Sn—Hf—Zn-based oxide, an In—Hf—Al—Zn-based oxide, or an In—Ga-basedoxide can be used.

Note that here, an In—Ga—Zn-based oxide means an oxide containing In,Ga, and Zn as its main components and there is no limitation on theratio of In to Ga and Zn. Furthermore, a metal element in addition toIn, Ga, and Zn may be contained.

For example, a semiconductor layer containing polycrystalline siliconthat is crystallized by treatment such as laser annealing can be used inthe transistor 502 t and the transistor 503 t illustrated in FIG. 7(B).

The structure in which top-gate transistors are used in the displayportion 501 is illustrated in FIG. 7(C).

For example, a semiconductor layer containing polycrystalline silicon, asingle crystal silicon film that is transferred from a single crystalsilicon substrate, or the like can be used in the transistor 502 t andthe transistor 503 t illustrated in FIG. 7(C).

Note that this embodiment can be combined with the other embodiments inthis specification as appropriate.

Embodiment 4

In this embodiment, a structure of a foldable touch panel that can beused for the information processing device of one embodiment of thepresent invention will be described with reference to FIG. 8.

FIG. 8 is a cross-sectional view of a touch panel 500B.

The touch panel 500B described in this embodiment is different from thetouch panel 500 described in Embodiment 3 in that the display portion501 that displays supplied image information on the side where thetransistors are provided is included and that the touch sensor isprovided on the substrate 510 side of the display portion. Differentstructures will be described in detail here, and the above descriptionis referred to for portions that can use similar structures.

<Display Portion>

The display portion 501 includes a plurality of pixels arranged in amatrix. Each of the pixels includes a display element and a pixelcircuit driving the display element.

<Structure of Pixel>

A pixel includes the sub-pixel 502R, and the sub-pixel 502R includes thelight-emitting module 580R.

The sub-pixel 502R includes the first light-emitting element 550R andthe pixel circuit including the transistor 502 t that can supplyelectric power to the first light-emitting element 550R.

The light-emitting module 580R includes the first light-emitting element550R and an optical element (e.g., the first coloring layer 567R).

The first light-emitting element 550R includes a lower electrode, anupper electrode, and a layer containing a light-emitting organiccompound between the lower electrode and the upper electrode.

The light-emitting module 580R includes the first coloring layer 567R inthe light extraction direction. The coloring layer transmits light witha particular wavelength, and a layer that selectively transmits light ofred, green, blue, or the like can be used, for example. Note that aregion that transmits light emitted from the light-emitting element asit is may be provided in another sub-pixel.

The first coloring layer 567R is in a position overlapping with thefirst light-emitting element 550R. The first light-emitting element 550Rshown in FIG. 8(A) emits light to the side where the transistor 502 t isprovided. Accordingly, part of light emitted from the firstlight-emitting element 550R passes through the first coloring layer 567Rand is emitted to the outside of the light-emitting module 580R asindicated by an arrow in the drawing. The information processing deviceof one embodiment of the present invention includes the first film 102in the direction of the arrow.

<Structure of Display Portion>

The display portion 501 includes the light-blocking layer 567BM in thelight extraction direction. The light-blocking layer 567BM is providedto surround the coloring layer (e.g., the first coloring layer 567R).

The display portion 501 includes the insulating film 521. The insulatingfilm 521 covers the transistor 502 t. Note that the insulating film 521can be used as a layer for reducing unevenness caused by the pixelcircuits. A stacked-layer film including a layer that can inhibitdiffusion of impurities can be used as the insulating film 521. This caninhibit a reduction in the reliability of the transistor 502 t or thelike due to, for example, impurities diffused from the first coloringlayer 567R.

<Touch Sensor>

The touch sensor 595 is provided on the substrate 510 side of thedisplay portion 501 (see FIG. 8(A)).

The resin layer 597 is positioned between the substrate 510 and thesubstrate 590 and bonds the display portion 501 and the touch sensor 595together.

Modification Example 1 of Display Portion

A variety of transistors can be used in the display portion 501.

The structure in which bottom-gate transistors are used in the displayportion 501 is illustrated in FIG. 8(A) and FIG. 8(B).

For example, a semiconductor layer containing an oxide semiconductor,amorphous silicon, or the like can be used in the transistor 502 t andthe transistor 503 t illustrated in FIG. 8(A). A pair of gate electrodesmay be provided so that a region of a transistor where a channel isformed is sandwiched therebetween. This can reduce variations incharacteristics of the transistors and increase the reliability.

For example, a semiconductor layer containing polycrystalline silicon orthe like can be used in the transistor 502 t and the transistor 503 tillustrated in FIG. 8(B).

The structure in which top-gate transistors are used in the displayportion 501 is illustrated in FIG. 8(C).

For example, a semiconductor layer containing polycrystalline silicon, atransferred single crystal silicon film, or the like can be used in thetransistor 502 t and the transistor 503 t illustrated in FIG. 8(C).

Note that this embodiment can be combined with the other embodiments inthis specification as appropriate.

Embodiment 5

In this embodiment, the rotation direction of the housing described inthe other embodiments will be described.

The panel substrate of one embodiment of the present invention ispreferably a touch panel. The display portion of the touch panelincludes a touch sensor, and a touch position is sensed when the firstfilm 102 is touched with a component with a thin tip, such as a pen or apencil, a finger, or the like. In other words, the panel substrate 101is protected by the first film 102.

In order to prevent fracture of the first film 102 due to the touch of acomponent with a thin tip on the first film 102, the first film 102needs to have high hardness. The hardness of the first film 102 can bemeasured by a pencil hardness test. In order to increase the hardness ofthe first film 102, it is preferable that the first film 102 havesufficient thickness and be formed using a material having sufficienthardness.

The panel substrate 101 includes a plurality of fragile portions 600Asuch as cracks caused by the touch of a component with a thin tip and aninterface between the wirings and the insulating film. Furthermore, thefirst film 102 includes a plurality of fragile portions 600B caused bythe touch of a component with a thin tip, for example.

The panel substrate 101 includes a flexible substrate 601, a flexiblesubstrate 602, and an element formation region 603 positionedtherebetween. A wiring formed of a metal layer, an inorganic insulatingfilm, and the like are formed in the element formation region 603, andan interface between them is present. Such an interface, a step, acrystal grain boundary, and the like tend to be the fragile portions600A. Thus, many fragile portions 600A are present in the elementformation region 603. When the fragile portions 600A in the elementformation region 603 fracture, an element (e.g., a transistor, acapacitor, or a wiring) included in the element formation region 603 isbroken in some cases.

For example, the panel substrate 101 is bent within the movable range ofthe housing and with the substrate 602 inside so that a bending moment604 is produced in the panel substrate 101 (see FIG. 12(A)).

When the panel substrate 101 is bent by the bending moment 604, tensilestress is applied, against the bending moment 604, to the substrate 601on the side where the panel substrate 101 is convexly bent. Furthermore,compressive stress is applied to the substrate 602 on the side where thepanel substrate 101 is concavely bent. Note that neither tensile stressnor compressive stress is applied to a surface near the center of thepanel substrate 101; this surface is referred to as a neutral surface605.

The level of stress on the neutral surface 605 of the panel substrate101 is 0, tensile stress linearly increases toward the surface of thepanel substrate 101 on the substrate 601 side, and compressive stresslinearly increases toward the surface of the panel substrate 101 on thesubstrate 602 side. Note that each stress is the maximum at the surfaceof the panel substrate 101, and the stress on the surface of the panelsubstrate 101 is referred to as the bending stress of the panelsubstrate 101.

When tensile stress is applied to the fragile portions 600A, generationof cracks starts from the fragile portions 600A and the fragile portions600A trigger fracture. By contrast, when compressive stress is appliedto the fragile portions 600A, the fragile portions 600A are crushed andthus are less likely to trigger fracture.

Since the element formation region 603 has a thickness, the elementformation region 603 cannot be formed only in the neutral surface 605;however, when the element formation region 603 is formed in the vicinityof the neutral surface 605, bending stress applied to the elementformation region 603 can be reduced. Furthermore, stress applied to theelement formation region 603 is desirably 0 or in the compressiondirection. In other words, a structure is preferable in which the panelsubstrate includes the element formation region 603 inward from theneutral surface 605. Thus, cracks are less likely to be generated in thefilm included in the element formation region 603 even when the panelsubstrate 101 is inwardly bent.

The information processing device of the present invention includes thefirst film 102 (see FIG. 12(B)). The first film 102 is not fixed to thepanel substrate 101. The panel substrate 101 is bent so that the firstfilm 102 is on the concave side. Accordingly, the display portion of thetouch panel can be protected. Alternatively, for example, in the casewhere an external force 606 is applied to the panel substrate 101 fromthe first film 102 side, the neutral surface 605 of the panel substrate101 moves toward the first film 102 side; however, a reduction in theexternal force 606 can relieve tensile stress applied to the elementformation region 603. Alternatively, fracture and cracks in the elementformation region 603 can be prevented.

Alternatively, the first film 102 has flexibility and includes a hardcoat layer on a surface different from the surface that is in contactwith the panel substrate 101. Thus, the panel substrate 101 can beprotected from a component with a thin tip, such as a pen or a pencil.Alternatively, even when the panel substrate 101 is bent so that thehard coat layer is placed inward, stress applied to the hard coat layercan be always 0 or in the compression direction.

The information processing device of the present invention includes thefirst housing, the second housing, the panel substrate 101, and thefirst film 102. The first housing is connected to the second housing soas to be rotatable, the first film 102 includes a surface that is incontact with the panel substrate 101, and the panel substrate 101includes the element formation region 603 closer to the first film 102than the neutral surface is, with the surface convexly bent. The firstfilm 102 includes the hard coat layer on the panel substrate 101 side.

In the information processing device of one embodiment of the presentinvention, the first housing is connected to the second housing so as tobe rotatable around the rotation axis within a predetermined movablerange, and the predetermined movable range controls the rotation so thatthe surface of the first film 102 on the panel substrate 101 side is aflat surface or has a convex shape. Accordingly, in the case where thefirst housing rotates around the rotation axis, generation of tensilestress in the element formation region 603 or the hard coat layer can beprevented. Alternatively, the fracture of the element formation region603 can be prevented. Alternatively, the fracture of the hard coat layercan be prevented.

A material having flexibility and a visible-light-transmitting propertycan be used for the first film 102. Examples of the material includepolyester resins such as polyethylene terephthalate (PET) andpolyethylene naphthalate (PEN), a polyacrylonitrile resin, a polyimideresin, a polymethyl methacrylate resin, a polycarbonate (PC) resin, apolyethersulfone (PES) resin, a polyamide resin, a cycloolefin resin, apolystyrene resin, a polyamide imide resin, a polyvinyl chloride resin,and a polytetrafluoroethylene (PTFE) resin. In particular, a materialwith a low thermal expansion coefficient is preferably used, and forexample, a polyamide imide resin, a polyimide resin, or PET with athermal expansion coefficient of 30×10⁻⁶/K or less can be suitably used.Furthermore, a substrate in which a glass fiber is impregnated with anorganic resin or a substrate whose thermal expansion coefficient isreduced by mixing an organic resin with an inorganic filler can be used.A substrate using such a material is lightweight, and thus a displaypanel using the substrate can also be lightweight.

As a material of the hard coat layer of the first film 102, athermosetting resin or the like can be used. For example, an epoxyresin, a phenol resin, an unsaturated polyester resin, a urea resin, amelamine resin, a diallyl phthalate resin, a silicon resin, a vinylester resin, polyimide, or polyurethane can be used. These materials arerigid and resistant to heat and a solvent, and thus are effective interms of surface protection. As the material of the hard coat layer ofthe first film 102, urethane acrylate is desirably used, for example.

The hard coat layer of the first film 102 preferably contains metaloxide particles such as a silica particle and an alumina particle. Thefirst film 102 is preferably coated with alumina. The first film 102 mayhave a structure in which a plurality of different materials arestacked. For example, a film having a structure in which a PET film witha thickness of 75 μm is stacked over the hard coat layer with athickness of 27 μm can be used.

The surface of the first film 102 is preferably processed so that anappropriate friction with a finger or the like touching the surface isgenerated. For example, appropriate unevenness (texture) may be providedon the first film 102.

In the case of moving a finger touching the first film 102, anexcessively large friction between the finger and the first film 102changes the form of the fingertip. Accordingly, it is difficult toperform input using fine movement of the fingertip. Examples of amaterial that generates an excessively large friction include glass witha surface that is sufficiently polished to be flat. By contrast, whenthe friction between the finger and the first film 102 is too small, thefinger's sense of touch on the surface is lost.

As a method for generating an appropriate friction on the surface of thefirst film 102, a film with a surface provided with silica particles orthe like can be used as the first film 102. Accordingly, the frictionbetween the finger and the first film 102 can have an appropriate level.

Note that this embodiment can be combined with the other embodiments inthis specification as appropriate.

Embodiment 6

In this embodiment, a method for manufacturing a foldable device thatcan be used in the information processing device of one embodiment ofthe present invention or electronic devices will be described withreference to FIG. 9 to FIG. 11. Note that examples of the foldabledevice include a display device, a light-emitting device, and an inputdevice. Examples of the input device include a touch sensor and a touchpanel. Examples of the light-emitting device include an organic EL paneland a lighting device. Examples of the display device include an organicEL panel and a liquid crystal display device. Note that a function ofthe input device such as a touch sensor may be provided in a displaydevice or a light-emitting device. For example, a counter substrate(e.g., a substrate not provided with a transistor) included in a displaydevice or a light-emitting device may be provided with a touch sensor.Alternatively, an element substrate (e.g., a substrate provided with atransistor) included in a display device or a light-emitting device maybe provided with a touch sensor. Alternatively, a counter substrateincluded in a display device or a light-emitting device and an elementsubstrate included in a display device or a light-emitting device may beprovided with touch sensors.

First, a separation layer 703 is formed over a formation substrate 701,and a layer to be separated 705 is formed over the separation layer 703(FIG. 9(A)). Furthermore, a separation layer 723 is formed over aformation substrate 721, and a layer to be separated 725 is formed overthe separation layer 723 (FIG. 9(B)).

For example, when a tungsten film is used as the separation layer, atungsten oxide film can be formed between the tungsten film and thelayer to be separated by an oxidation method performed on the tungstenfilm, such as plasma treatment with a gas containing oxygen such as N₂O,annealing in a gas atmosphere containing oxygen, or forming a tungstenoxide film by a method such as sputtering in a gas atmosphere containingoxygen.

At the time of a separating and transferring process of the tungstenoxide film, it is preferable that tungsten oxide mainly have acomposition in which the ratio of oxygen to tungsten is lower than 3. Ina homologous series of tungsten oxides such as W_(n)O_((3n−1)) andW_(n)O_((3n−2)) where n is a natural number greater than or equal to 1,shear is easily caused by overheating of a crystal optical shear planetherein. When the tungsten oxide film is formed by N₂O plasma treatment,the layer to be separated can be separated from the substrate with aweak force.

Alternatively, the tungsten oxide film can be directly formed withoutforming a tungsten film. For example, only the tungsten oxide film maybe formed as the separation layer by performing plasma treatment on asufficiently thin tungsten film with a gas containing oxygen, annealinga sufficiently thin tungsten film in a gas atmosphere containing oxygen,or forming the tungsten oxide film by a method such as sputtering in agas atmosphere containing oxygen.

When the separation is caused at the interface between the tungsten filmand the tungsten oxide film or inside the tungsten oxide film, thetungsten oxide film remains on the side of the layer to be separated, insome cases. Then, the remaining tungsten oxide film might adverselyaffect the properties of a transistor. Thus, a step of removing thetungsten oxide film is preferably performed after the step of separatingthe separation layer and the layer to be separated. Note that with theabove method for separation from the substrate, N₂O plasma treatment isnot necessarily performed, which can eliminate the step of removing thetungsten oxide film. In that case, the device can be manufactured moreeasily.

In one embodiment of the present invention, a tungsten film with athickness greater than or equal to 0.1 nm and less than 200 nm is usedover the substrate.

Other than a tungsten film, a film containing molybdenum, titanium,vanadium, tantalum, silicon, aluminum, or an alloy thereof may be usedas the separation layer. Furthermore, a stacked-layer structure of sucha film and its oxide film may be used. The separation layer is notlimited to an inorganic film, and an organic film such as polyimide maybe used.

In the case where an organic resin is used for the separation layer, aprocess needs to be performed at lower than or equal to 350° C. to uselow-temperature polysilicon in a semiconductor layer. Thus,dehydrogenation baking for silicon crystallization, hydrogenation fortermination of defects in silicon, activation of a doped region, or thelike cannot be performed sufficiently, which limits the performance. Onthe other hand, in the case where an inorganic film is used, thedeposition temperature is not limited to 350° C., and excellentcharacteristics can be obtained.

In the case where an organic resin is used for the separation layer, theorganic resin or a functional element is damaged in some cases by laserirradiation for crystallization, whereas in the case where an inorganicfilm is used for the separation layer, such a problem is not caused,which is preferable.

Furthermore, in the case where an organic resin is used for theseparation layer, the organic resin is shrunk by laser irradiation forseparating the resin and contact failure is caused in the contactportion of the terminal of an FPC or the like, which makes it difficultfor functional elements with many terminals in a high-definition displayor the like to be separated and transferred with high yield. There is nosuch limitation in the case where an inorganic film is used for theseparation layer, and functional elements with many terminals in ahigh-definition display or the like can be separated and transferredwith high yield.

In the method for separating a functional element from a substrate ofone embodiment of the present invention, an insulating layer and atransistor can be formed over a formation substrate at lower than orequal to 600° C. This allows the use of high-temperature polysilicon fora semiconductor layer. In that case, with use of a conventional line forhigh-temperature polysilicon, a semiconductor device with a highoperation speed, a high gas barrier property, and high reliability canbe mass-produced. In that case, with use of the insulating layer and thetransistor formed through a process at 600° C. or lower, insulatinglayers with a high gas barrier property formed under the depositioncondition of lower than or equal to 600° C. can be placed above andbelow an organic EL element. Accordingly, entry of impurities such asmoisture into the organic EL element or the semiconductor layer isinhibited, whereby an extraordinarily reliable light-emitting device canbe obtained as compared with the case of using an organic resin or thelike for the separation layer.

Alternatively, the insulating layer and the transistor can be formedover the formation substrate at 500° C. or lower. In that case,low-temperature polysilicon or an oxide semiconductor can be used forthe semiconductor layer, and mass production is possible with use of aconventional production line for low-temperature polysilicon. Also inthat case, with use of the insulating layer and the transistor formedthrough the process at 500° C. or lower, insulating layers with a highgas barrier property formed under the deposition condition of 500° C. orlower can be placed above and below the organic EL element. Accordingly,the entry of impurities such as moisture into the organic EL element orthe semiconductor layer is inhibited, whereby a highly reliablelight-emitting device can be obtained as compared with the case of usingan organic resin or the like for the separation layer.

Alternatively, the insulating layer and the transistor can be formedover the formation substrate at 400° C. or lower. In that case,amorphous silicon or an oxide grain semiconductor can be used for thesemiconductor layer, and mass production is possible with use of aconventional production line for amorphous silicon. Also in that case,with use of the insulating layer and the transistor formed through theprocess at 400° C. or lower, insulating layers with a high gas barrierproperty formed under the deposition condition of 400° C. or lower canbe placed above and below the organic EL element. Accordingly, the entryof impurities such as moisture into the organic EL element or thesemiconductor layer is inhibited, whereby a highly reliablelight-emitting device can be obtained as compared with the case of usingan organic resin or the like for the separation layer.

Next, the formation substrate 701 and the formation substrate 721 arebonded together by using a bonding layer 707 and a frame-like bondinglayer 711 so that the surfaces over which the layers to be separated areformed face each other, and then, the bonding layer 707 and theframe-like bonding layer 711 are cured (FIG. 9(C)). Here, the frame-likebonding layer 711 and the bonding layer 707 positioned inward from theframe-like bonding layer 711 are provided over the layer to be separated725 and after that, the formation substrate 701 and the formationsubstrate 721 face each other and are bonded together.

Note that the formation substrate 701 and the formation substrate 721are preferably bonded together in a reduced-pressure atmosphere.

Note that although FIG. 9(C) shows the case where the separation layer703 and the separation layer 723 are different in size, separationlayers having the same size as shown in FIG. 9(D) may be used.

The bonding layer 707 is placed to overlap with the separation layer703, the layer to be separated 705, the layer to be separated 725, andthe separation layer 723. Then, end portions of the bonding layer 707are preferably positioned inward from end portions of at least one ofthe separation layer 703 and the separation layer 723 (one that isdesirably separated from the substrate first). In that case, strongadhesion between the formation substrate 701 and the formation substrate721 can be inhibited; thus, a decrease in the yield of a subsequentseparating process can be inhibited.

Next, a first trigger 741 for separation from the substrate is formed bylaser light irradiation (FIGS. 10(A) and 10(B)).

Either the formation substrate 701 or the formation substrate 721 may beseparated first. In the case where the separation layers differ in size,a substrate over which a larger separation layer is formed may beseparated first or a substrate over which a smaller separation layer isformed may be separated first. In the case where an element such as asemiconductor element, a light-emitting element, or a display element isformed over only one of the substrates, the substrate on which theelement is formed may be separated first or the other substrate may beseparated first. Here, an example in which the formation substrate 701is separated first is described.

A region where the bonding layer 707 in a cured state or the frame-likebonding layer 711 in a cured state, the layer to be separated 705, andthe separation layer 703 overlap with one another is irradiated withlaser light. Here, the case where the bonding layer 707 is in a curedstate and the frame-like bonding layer 711 is not in a cured state isexemplified, and the bonding layer 707 in a cured state is irradiatedwith laser light (see an arrow P3 in FIG. 10(A)).

Part of the layer to be separated 705 is removed, whereby the firsttrigger 741 for separation from the substrate can be formed (see aregion surrounded by a dotted line in FIG. 10(B)). At this time, notonly the layer to be separated 705 but also the separation layer 703,the bonding layer 707, or another layer in the layer to be separated 705may be partly removed.

It is preferred that laser light irradiation be performed from the sideof the substrate provided with the separation layer that is desirablyseparated. In the case where a region where the separation layer 703 andthe separation layer 723 overlap with each other is irradiated withlaser light, the formation substrate 701 and the separation layer 703can be selectively separated by cracking only the layer to be separated705 of the layer to be separated 705 and the layer to be separated 725(see the region surrounded by the dotted line in FIG. 10(B)).

In the case where the region where the separation layer 703 and theseparation layer 723 overlap with each other is irradiated with laserlight, it might be difficult to selectively separate one of theformation substrates when a trigger for separation from the substrate isformed in each of the layer to be separated 705 on the separation layer703 side and the layer to be separated 725 on the separation layer 723side. Therefore, laser light irradiation conditions are sometimesrestricted so that only one of the layers to be separated is cracked.The method for forming the first trigger 741 for separation from thesubstrate is not limited to laser light irradiation, and the firsttrigger 741 may be formed with a sharp knife such as a cutter.

Then, the layer to be separated 705 and the formation substrate 701 areseparated from each other from the formed first trigger 741 forseparation from the substrate (FIGS. 10(C) and 10(D)). Consequently, thelayer to be separated 705 can be transferred from the formationsubstrate 701 to the formation substrate 721.

The layer to be separated 705 that is separated from the formationsubstrate 701 in the step shown in FIG. 10(D) is bonded to a substrate731 with the use of a bonding layer 733, and the bonding layer 733 iscured (FIG. 11(A)).

Next, a second trigger 743 for separation from the substrate is formedwith a sharp knife such as a cutter (FIGS. 11(B) and 11(C)). A methodfor forming the second trigger 743 for separation from the substrate isnot limited to a sharp knife such as a cutter, and the second trigger743 may be formed by laser light irradiation or the like.

In the case where the substrate 731 on the side where the separationlayer 723 is not provided can be cut with a knife or the like, a cut maybe made in the substrate 731, the bonding layer 733, and the layer to beseparated 725 (see arrows P5 in FIG. 11(B)). Consequently, part of thelayer to be separated 725 can be removed; thus, the second trigger 743for separation from the substrate can be formed (see a region surroundedby a dotted line in FIG. 11(C)).

In the case where the formation substrate 721 and the substrate 731 arebonded together with the use of the bonding layer 733 in a region notoverlapping with the separation layer 723 as shown in FIGS. 11(B) and11(C), the yield of a subsequent process of separation from thesubstrate might be decreased depending on the degree of adhesion betweenthe formation substrate 721 side and the substrate 731 side. Therefore,a cut is preferably made in a frame shape in a region where the bondinglayer 733 in a cured state and the separation layer 723 overlap witheach other to form the second trigger 743 for separation from thesubstrate in the form of a solid line. This can increase the yield ofthe process of separation from the substrate.

Then, the layer to be separated 725 and the formation substrate 721 areseparated from each other from the formed second trigger 743 forseparation from the substrate (FIG. 11(D)). Accordingly, the layer to beseparated 725 can be transferred from the formation substrate 721 to thesubstrate 731.

For example, in the case where a tungsten oxide film that is tightlyanchored by N₂O plasma or the like is formed on an inorganic film suchas a tungsten film, adhesion can be relatively high in deposition. Afterthat, when a separation trigger is formed, cleavage occurs therefrom,whereby a layer to be separated can be easily separated from a formationsubstrate and transferred to a substrate.

The formation substrate 721 and the layer to be separated 725 may beseparated from each other by filling the interface between theseparation layer 723 and the layer to be separated 725 with a liquidsuch as water. A portion between the separation layer 723 and the layerto be separated 725 absorbs a liquid through a capillary action;accordingly, an adverse effect on a functional element such as an FETincluded in the layer to be separated 725 due to static electricitycaused at the time of separation from the substrate (e.g., damage to asemiconductor element from static electricity) can be inhibited.

In the case where a bond of M-O—W (M is a given element) is divided byapplication of physical force, a liquid is absorbed into the portion,whereby the bond becomes bonds of M-OH and HO—W with a longer bonddistance and the separation can be promoted.

Note that a liquid may be sprayed in the form of mist or vapor. As theliquid, pure water, an organic solvent, or the like can be used, and aneutral, alkali, or acid aqueous solution, an aqueous solution in whicha salt is dissolved, or the like may be used.

The temperature of the liquid and the substrate at the time of dynamicseparation is set in the range from room temperature to 120° C., andpreferably set from 60° C. to 90° C.

In the method for separation from a substrate of one embodiment of thepresent invention described above, separation of the formation substrateis performed after the second trigger 743 for separation from thesubstrate is formed with a sharp knife or the like so that theseparation layer and the layer to be separated are made in an easilyseparable state. This can improve the yield of the process of separationfrom the substrate.

Furthermore, a pair of formation substrates each provided with a layerto be separated are bonded together in advance and then the formationsubstrates are individually separated, so that bonding of a substratewith which a device is to be manufactured can be performed. Therefore,formation substrates having low flexibility can be bonded together whenthe layers to be separated are bonded together, whereby alignmentaccuracy at the time of bonding can be improved as compared with thecase where flexible substrates are bonded together.

In the method for separation from a substrate of one embodiment of thepresent invention, a first layer and a second layer from which hydrogenis released by heating are provided in a layer to be separated that isprovided over an oxide layer. Moreover, WO₃ in the oxide layer can bereduced by hydrogen released by heat treatment from the layer to beseparated, so that the oxide layer containing a large amount of WO₂ canbe formed. Consequently, separability from the substrate can beimproved.

This embodiment can be implemented in combination with the otherembodiments and example described in this specification as appropriate.

Embodiment 7

In this embodiment, a structure of an electronic device of oneembodiment of the present invention will be described with reference toFIG. 13.

<Electronic Device>

FIG. 13 shows a foldable electronic device 920. The electronic device920 shown in FIG. 13 includes a housing 921 a, a housing 921 b, adisplay portion 922, a hinge 923, and the like. The display portion 922is incorporated in the housing 921 a and the housing 921 b.

The housing 921 a and the housing 921 b are rotatably joined together bythe hinge 923. The electronic device 920 can be changed in its formbetween a state where the housing 921 a and the housing 921 b are closedand a state where they are opened, as shown in FIG. 13. Thus, theelectronic device has high portability when carried and excellentvisibility when used because of its large display region.

The hinge 923 preferably includes a locking mechanism so that an angleformed between the housing 921 a and the housing 921 b does not becomean angle larger than a predetermined angle when they are opened. Forexample, an angle at which they become locked (they are not opened anyfurther) is preferably greater than or equal to 90° and less than 180°and can be typically 90°, 120°, 135°, 150°, 175°, or the like.Accordingly, the convenience, the safety, and the reliability can beimproved.

In the electronic device 920, the flexible display portion 922 isprovided across the housing 921 a and the housing 921 b which are joinedtogether by the hinge 923.

In the electronic device 920, the display portion 922 is held in a stateof being greatly curved with the housing 921 a and the housing 921 bopen. For example, the display portion 922 is held with a curvatureradius greater than or equal to 1 mm and less than or equal to 50 mm,and preferably greater than or equal to 5 mm and less than or equal to30 mm. Part of the display portion 922 can perform display in a curvedsurface shape since pixels are continuously arranged from the housing921 a to the housing 921 b.

Since the hinge 923 includes the above-described locking mechanism,excessive force is not applied to the display portion 922; thus,breakage of the display portion 922 can be prevented. Consequently, ahighly reliable electronic device can be obtained.

The display portion 922 functions as a touch panel and can be operatedwith a finger, a stylus, or the like.

One of the housing 921 a and the housing 921 b is provided with awireless communication module, and data can be transmitted and receivedthrough a computer network such as the Internet, a LAN (Local AreaNetwork), or Wi-Fi (Wireless Fidelity: registered trademark). One of thehousing 921 a and the housing 921 b may be provided with a keyboard, ahardware button, a pointing device, an illuminance sensor, an imagingdevice, an audio input device, an eye-gaze input device, or a posedetection device.

The electronic device of one embodiment of the present invention canhave various applications when the size of the display portion 922 ischanged as appropriate. Examples of the electronic device include aportable information terminal that is easy to carry.

For example, text information can be displayed on the display portion922; thus, the electronic device can be used as an e-book reader. Forexample, the display portion can be used as a textbook, which has astructure in which A4 size is folded in two. The display portion 922 canalso display a still image or a moving image.

At least part of this embodiment can be implemented in combination withthe other embodiments described in this specification as appropriate.

Reference numerals 101: panel substrate 102: film 103: film 104-1:housing 104-1A: first part 104-1B: second part 104-2: housing 104-2A:first part 104-2B: second part 105-1: hinge 106: circuit board 107: FPC108-1: slit 108-2: slit 109: socket 110: end portion 111: end portion116: support portion 117: support portion 300: touch panel 301: displayportion 302: pixel 302B: sub-pixel 302G: sub-pixel 302R: sub-pixel 302t:transistor 303c: capacitor 303g(1): scan line driver circuit 303g(2):imaging pixel driver circuit 303s(1): image signal line driver circuit303s(2): imaging signal line driver circuit 303t: transistor 308:imaging pixel 308p: photoelectric conversion element 308t: transistor309: FPC 310: substrate 310a: barrier film 310b: substrate 310c: resinlayer 311: wiring 319: terminal 321: insulating film 328: partition 329:spacer 350R: light-emitting element 351R: lower electrode 352: upperelectrode 353: layer 353a: light-emitting unit 353b: light-emitting unit354: intermediate layer 360: sealant 367BM: light-blocking layer 367p:anti-reflective layer 367R: coloring layer 370: counter substrate 370a:barrier film 370b: base 370c: resin layer 380B: light-emitting module380G: light-emitting module 380R: light-emitting module 400: touch panel401(1): region 401(2): region 406: line segment 407: line segment 500:touch panel 500B: touch panel 501: display portion 502R: sub-pixel 502t:transistor 503c: capacitor 503g: scan line driver circuit 503t:transistor 509: FPC 510: substrate 510a: barrier film 510b: substrate510c: resin layer 511: wiring 519: terminal 521: insulating film 528:partition 550R: light-emitting element 560: sealant 567BM:light-blocking layer 567p: anti-reflective layer 567R: coloring layer570: substrate 570a: barrier film 570b: substrate 570c: resin layer580R: light-emitting module 590: substrate 591: electrode 592: electrode593: insulating layer 594: wiring 595: touch sensor 597: resin layer598: wiring 599: connection layer 600A: fragile portion 600B: fragileportion 601: substrate 602: substrate 603: element formation region 604:bending moment 605: neutral surface 701: formation substrate 703:separation layer 705: layer to be separated 707: bonding layer 711:frame-like bonding layer 721: formation substrate 723: separation layer725: layer to be separated 731: substrate 733: bonding layer 741: firsttrigger for separation 743: second trigger for separation 920:electronic device 921a: housing 921b: housing 922: display portion 923:hinge

1. An information processing device comprising: a touch panel, the touchpanel comprising: a first flexible substrate; a second flexiblesubstrate; and an element formation region between the first flexiblesubstrate and the second flexible substrate, wherein a display portionof the touch panel comprises a touch sensor, wherein a touch is sensedwhen a first film is touched, wherein the first film is not fixed to thetouch panel, wherein the first film is on a concave side, when the touchpanel is bent, and wherein a neutral surface of the touch panel movestoward the first film side when an external force is applied to thetouch panel from the first film side.
 2. The information processingdevice according to claim 1, wherein the first film has flexibility andcomprises a hard coat layer on a surface different from a surface incontact with the touch panel.
 3. The information processing deviceaccording to claim 2, wherein, when the panel substrate is bent so thatthe hard coat layer is placed inward, stress applied to the hard coatlayer is always 0 or in a compression direction.
 4. The informationprocessing device according to claim 3, further comprising a firsthousing; and a second housing, the second housing is connected to thefirst housing so as to be rotatable, wherein the element formationregion is closer to the first film than the neutral surface is, with thesurface convexly bent.
 5. The information processing device according toclaim 4, wherein a material used for the first film is selected from apolyester resin, a polyacrylonitrile resin, a polyimide resin, apolymethyl methacrylate resin, a polycarbonate resin, a polyethersulfoneresin, a polyamide resin, a cycloolefin reson, a polystyrene resin, apolyamide imide resin, a glass fiber impregnated with an organic resin,and an organic resin mixed with an inorganic filler.
 6. The informationprocessing device according to claim 5, wherein a material used for thehard coat layer of the first film is selected from an epoxy resin, aphenol resin, an unsaturated polyester resin, a urea resin, a melamineresin, a diallyl phthalate resin, a silicon resin, a vinyl ester resin,polyimide, and polyurethane.
 7. The information processing deviceaccording to claim 6, wherein the material used for the hard coat layerof the first film is urethane acrylate.
 8. The information processingdevice according to claim 6, wherein the material used for the hard coatlayer of the first film contains metal oxide particles
 9. Theinformation processing device according to claim 8, wherein the firstfilm is coated with alumina, and wherein a surface of the first film isprovided with a texture.
 10. The information processing device accordingto claim 1, further comprising a hinge, wherein the hinge comprises arotation axis, wherein the first housing comprises a first slit, whereinthe second housing comprises a second slit, wherein a region of thefirst film is stored in one or both of the first slit and the secondslit, and wherein the first film is configured to slide along the secondslit.
 11. An information processing device comprising: a first film; asecond film; and a touch panel, the touch panel comprising: a firstflexible substrate; a second flexible substrate; and an elementformation region between the first flexible substrate and the secondflexible substrate, wherein a display portion of the touch panelcomprises a touch sensor, wherein a touch is sensed when the first filmis touched, wherein the first film is not fixed to the touch panel,wherein the first film is on a concave side, when the touch panel isbent, wherein a neutral surface of the touch panel moves toward thefirst film side when an external force is applied to the touch panelfrom the first film side, and wherein the touch panel comprises a regionpositioned between the first film and the second film.
 12. Theinformation processing device according to claim 11, wherein the firstfilm has flexibility and comprises a hard coat layer on a surfacedifferent from a surface in contact with the touch panel.
 13. Theinformation processing device according to claim 12, wherein, when thepanel substrate is bent so that the hard coat layer is placed inward,stress applied to the hard coat layer is always 0 or in a compressiondirection.
 14. The information processing device according to claim 13,further comprising a first housing; and a second housing, the secondhousing is connected to the first housing so as to be rotatable, whereinthe element formation region is closer to the first film than theneutral surface is, with the surface convexly bent.
 15. The informationprocessing device according to claim 14, wherein a material used for thefirst film is selected from a polyester resin, a polyacrylonitrileresin, a polyimide resin, a polymethyl methacrylate resin, apolycarbonate resin, a polyethersulfone resin, a polyamide resin, acycloolefin reson, a polystyrene resin, a polyamide imide resin, a glassfiber impregnated with an organic resin, and an organic resin mixed withan inorganic filler.
 16. The information processing device according toclaim 15, wherein a material used for the hard coat layer of the firstfilm is selected from an epoxy resin, a phenol resin, an unsaturatedpolyester resin, a urea resin, a melamine resin, a diallyl phthalateresin, a silicon resin, a vinyl ester resin, polyimide, andpolyurethane.
 17. The information processing device according to claim16, wherein the material used for the hard coat layer of the first filmis urethane acrylate.
 18. The information processing device according toclaim 16, wherein the material used for the hard coat layer of the firstfilm contains metal oxide particles
 19. The information processingdevice according to claim 18, wherein the first film is coated withalumina, and wherein a surface of the first film is provided with atexture.
 20. The information processing device according to claim 11,further comprising a hinge, wherein the hinge comprises a rotation axis,wherein the first housing comprises a first slit, wherein the secondhousing comprises a second slit, wherein a region of the first film isstored in one or both of the first slit and the second slit, and whereinthe first film is configured to slide along the second slit.